Continuous sheet facsimile recorder



Peli. 22, 1938.

w. G. H. FlNcH CONTINUOUS SHEET FACSIMILE RECORDER 3 Sheets-Sheet 1Original Filed Feb. 3, 1937 l I @3 l Hi Irv m. ,Iii Q. NIT@ mw mm E NN.uw l um. E- QE ww EN \1\\\\\\ `mvENrOR. )Cfnch Willmrl Feb. 22, 1938. w.G. H. FlNcH 2,109,109

CONTINUOUS SHEET FACSIMILE RECORDER original Filed Feb. s, 1957 5sheets-sheet 2 ATTORNEY.

Feb. 22, 1938. w. G. H. FlNcH i 2,109,109

CONTINUOUS SHEET FACSIMILE RECORDER Original Filed Feb. 5, 193'? 3Sheets-Sheet 5 n 1N VENT OR, will; am'gj'nch ATTORNEY.

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Figure 6 is a top view Patented' Feb. 22, 1938 PATENT OFFICE 2,109,109CONTINUOUS SHEET FACSIMILE accomuna William G. H. Finch, Spily'tenDuyvil, N. Y". Continuation of application Serial No. 123,770,

February 3, 1937. 1937, Serial No. 132,690

Claims.

. This invention relates to facsimile systems and more particularlyrelates to improvements in facsimile receivers for recording pictures ormessages on a continuously fed record sheet.

This invention is a continuation of my copending application Serial No.123,779, illed February 3, 1937, entitled Continuous sheet 4facsimilesystem." In this co-pending application I have disclosed novel andsimplified mechanism particularly useful for rugged, compact and mobilefacsimile units, and have particularly de-l scribed their application toa transmitter unit. The present application relates to a receiver unitembodying the scanning and sheet feeding arrangements disclosed thereintogether with novel methods of and means for actuating the recordingstylus and maintaining synchronous movement between the transmitter andreceiver.

The mobile facsimile receiver of my present invention operates from aroll of treated paper and directly records the messages or picturesthereon, without intermediate photography processes. The simpliedmechanism results in a mobile receiver which is particularly useful foraircraft, ship and automobile, as well as for home reception and otherinstances where a compact and relatively inexpensive unit is required.

The objects of my present invention reside in ,providing a novelelectromechanical stylus for direct quality recording upon a recordsheet; to provide a novel translating unit which is electromagneticallybalanced' and substantially uniformly responsive to the frequency rangenecessary for quality black-white recording; and to provide` improvedmethods of and means for maintaining the receiver unit at synchronouspresent invention. y

Figure 2 is an elevational view of the receiver unit.

Figure 3 is a top view of the receiver unit.

Figure 4 is a perspective view of the electromechanical recorder withits elements detached.

Figure 5 is a cross-sectional view taken along l-I o! Figure 1 throughthe electromechanical recording unit.

of the recording unit This application March 24,

corresponding to the view taken along 6-6 in Figure 1.

Figure 7 is an enlarged cross-sectional view of a preferred arrangementfor the stylus mechanism.

Figure 8 is a cross-sectional view taken along 8-8 of Figure 7.

vligr9 is a perspective view of the assembled receiver unit. e

`Referring to the figures, and more particularly 10 to'Figures'l, 2, and3, I illustrate the facsimile receiver mounted on a cast iron base I0. Amotor II supplies the continuous drive for the operation of the scanningunit. Motor II .is preferably a constant speed direct current motor forl5 operation at a substantially constant speed. I prefer to employ amotor operable at 1800 revolutions per minute. By using a, batterysource for driving the motor aboard an aircraft or other vehicle, auniform speed of oper/ation is assured. 20

It is to be understood that a motor at the associated transmitter isoperated at the predetermined speed which corresponds to the scanningspeed of the system.

To facilitate maintaining the speed of motor II close to thepredetermined value over a relatively long period of operation, I preferto use a speed governing device appended thereto. In Figure 1 Iillustrate a mechanical speed governor I2 attached to the shaft I3extending from the 30 motor. By adjusting the position of the frictionpad Il against the disk I5 by means of thumb screw I6, the governor maybe set for the prede'- termined speed, which speed will besatisfactorily maintained over many days or even weeks of use. The diskI1, having alternate dark and light markings, is employed to adjust thegovernor I2 setting to the required speed with the aid of a tuning forkin the manner describedl in my copending application Serial No. 128,920,led 40 March 4, 1937.

I prefer to employ the synchronizing circuits and arrangements disclosedin my Reissue Patent No. 19,575, led May 21, i935 entitled Imagebroadcasting system and also disclosed in my Patent No. 2,047,863. Thissynchronizing system employs a synchronizing magnet I8 shown mountedupon motor il by bracket 20; an armature 2| for magnet I8 having aprojection 22;

and a single revolution positive clutch 23 co- 50 operatingwith theamature projection 22.

A synchronizing impulse is transmitted cyclically between the intervalsof the line by line recording, which impulses are impressed upon thesynchronizing magnet through connection leads 24 to attract the armature2| and projection 22 away from the single revolution clutch 23 to permitthe execution of a single scanning line in a manner to-be described inmore detail. I have omitted the electrical circuit connections forreceiving and producing the rectified impulse at magnet I8 since thesecircuits are clearly disclosed in my patents above referred to and arenot part of my present invention. employ such synchronizing systemwhereby the accurate phase positioning of each line is accuratelydetermined by means of cyclic synchronizing signals at the transmittersince the continuous sheet recording is more satisfactorily per-` formedby such regular phasing operations. Accordingly, the motor II speed neednot be precisely synchronous with the corresponding transmitter motorspeed but be substantially close to the predetermined speed as will beevident. The constant speed motor in combination with the mechanical oran equivalent electrical governor performs excellent picturesynchronizing and phasing for long periods of operation.

Motor II continuously drives the pinion 25 which is keyed to a sleeve 26surrounding the vertical shaft 21. The housing or driven member ofclutch 23 is integral with the sleeve 26 at the extended or shoulderportion 23 thereof. 'I'he sleeve 26 is rotatably supported in the casing23 of the motor` Il. The driven or interior portion l3l) of the positiveclutch 23 is secured to the vertical shaft 21 by a pin 3|. When theclutch 23 is in engaged condition. the continuously driven pinion 25drives the vertical rod 21 through the clutch 23. -A spring 32 biasesthe armature projection 22 against the periphery 33 of the clutch 23 todisengage the clutch at the end of a single revolution and maintainssuch disengagement until the synchronizingmagnet I8 is energized by thecyclic synchronizing impulse. I prefer to drive the motor I I at aslightly greater speed than the predetermined speed for example, in theratio of 10*1:100 to insure the disengagement of the clutch before theadvent of the synchronizing impulse. Cams 34, 35 are secured to the topof vvertical shaft 21 and cooperate with the synchronizing cam switch 36which switch is connected to the synchronizing electrical circuitv (notshown) by leads 31.

A gear 38 is attached to the bottom of the vertical rod 21. The gear 38operates the oscillating scanner arm-.40 which carries the stylus. Inthe illustrated arrangement, one oscillation comprising a single forwardand return movement of the scanner arm 40 is performed during onerevolution of the rod 21. A preferable scanning speed for this system issixty lines per minute correspondingl to cnerevolution per second of thevertically driven shaft 21. A cam 4I is used to execute the desiredmovement of the scanner arm 40. Cam 4| is connected to gear 42 whichmeshes with and is driven by gear 38. Cam 4I is rotatably supported onrod 43 which is aiiixed to the base I0 in bushing 44. A cam follower 45is actuated by the cam 4I. The follower 45 is connected to the verticalrod 46 which in turn is directly connected to the electromechanicalrecording unit 41. 'I'he cam and oscillatory motion mechanism 4I to 45is similar to the corresponding mechanism of the transmitter describedin more detail in my co-pending application Serial No. 123,770hereinabove referred to.

The base 43 of the recording unit 41 is keyed to the top of vertical rod46 and is accordingly oscillated therewith as will now be evident. The

I prefer to scanner arm 40 is secured to the magnetic casing structureof the recording unit 41. Arm 45ex tends from the magnetic unit 41 tothe record sheet 5I and supports the stylus rod 52. A steel point'53 iscarried at the end of rod 52 for direct recording on the record sheet 5Iin a manner to be described. 'I'he stylus is oscillated against therecord sheet 5I in accordance with facsimile signals. By maintainingsynchronous movement of the scanner arm 40 and by proper advancing orfeeding of the record sheet 5I, line by line past the scanning position,accurate reproductions are readily made thereon. 'I'he stylus point 53is preferably made of steel to resist wear. A heater coil 54 is wound atthe stylus tip. 'Ihe heater coil 54 is connected to a heating currentsupply by leads 55. A direct current of six to twelve volts is asuitable supply to maintain the stylus point 53 continuously heated forthe recording operation. The record sheet 5I in my preferred mobilefacsimile unit is a colored sheet having a wax coating. 'I'he waxcoating is melted along the portions at which the heated stylus 53operatesagainst the waxed surface. For black-white reproductions Iemploy a black paper coated on the recording surface with a layer ofwhite colored waxy substance. The Wax coating exists on the surfaceunder all weather conditions and is melted at the portions at which theheated stylus point 53 makes contact. The picture signals represent theblack and white markings and actuate the stylus rod 52 in a manner to bedescribed, to and fro against the sheet 5I to reproduce the picture. Thecontinuous record sheet 5I is arranged in a large roll 56, and is fedpast the stylus 53 in a positive manner a predetermined amount betweeneach scanning line.

The line by line sheet feeding mechanism is similar to the correspondingfeeding mechanism disclosed in my co-pending application Serial No.123,770 and comprises a rocker arm 51 actuated by a cam 58. The cam 58is secured to the vertical driven rod 21 which is rotated in accordancewith the scanning movements. The rocker arm 51 actuates a pawl andratchet arrangement 5l which rotates the -presser roller 60 to a degreesufficient to/advance the record sheet 5I by the distance betweensuccessive scanning lines. The advancing movement is executed once perrevolution of the rod 21 and corresponds to one scanning oscillation ofthe scanner arm 40. I prefer to employ sixty lines per inch whereby oneinch of the final picture is recorded in one minute.

The record sheet may be independently advanced Ey means of the handlelwhich operates the rollers 62. The operator may thus advance va recordedportion from the region of the stylus is a perspective illustration ofthe facsimile rev#` corder unit with the record sheet 5I containingpictures made thereon. The handle 6I is used tb 2,109,109 pivoted on rodss. Rod ss is supported in bushtified in a conventional manner andintroduced to the connection leads 18 of the coils 1|. The coils 1| arearranged concentric with and at opposite ends of the pivoted armature 53to variably magnetize the larmature and cause it to vibrate between thepole faces 12-12. The pole faces 12 are formed in Atwo C-shaped opposingportions inwardly tapered toward the armature 63. Permanent magnets13-13 are placed adjacent opposite sides of the pole pieces 12--12 tocreate a permanent magnetic field across the air gaps including thepivoted armature 53. A1- though my preferred illustration showspermanent magnets 13, it is evident that electromagnets may besubstituted therefor to produce the uniform direct current eld acrossthe pole faces 'I'he coils 1|-/-1| are preferably connected in seriesand the leads 10 for the coils 1| are directly connected to the outputof an electronic amplifier for the received facsimile signals.1 The coil1| may be connected in push-pull relation with a push-pull amplifieroutput stage or connected to a single tube amplifier output as desired.The single currents flowing through the coils 1|-1I superimpose avariable magnetic iield on the armature 63 and across the air gaps 14 tocorrespondingly oscillate the armature 53 about its pivotal support 65.The stylus arm 52, pivotally connected at 64 tothe armature 53 iscorrespondingly oscillated in accordance with the signals received. Thestylus point 53 is impinged against the record sheet 5| preferablyduring the black portions of the picture shading. By arranging` thecircuitsto send current through the coil 1| during the dark pictureportions, the styllw point 53 will be pressed against the record sheetduring such dark portions to melt the wax coating thereon and representa corresponding black or colored line on the reproduction.

A block 15 (Figure 1) is placed against the record sheet 5| opposite thescanning region to rigidly hold the sheet 5| in position during theexcursions of the stylus point 53 against the sheet. The block 15 isarcuate to correspond to the path of the oscillating scanning point. Theradial lines 18 on Figure 3 define the end portions of. the scanner arm4l! in its oscillation path. By holding the record sheet 5| in the'arcuate path 11 defined by the radius of the stylus, the sheet will beequidistant with respect to the stylus 53 at any point in its excursion.By adjusting the stylus point 53 to clear the record sheet 5|, signalsimpressed 'upon the electromagnetic system 41 will cause the styluspoint to. advance toward the sheet held in the arcuate path 11 andcorrespondingly mark the record sheet. Accordingly, a black-whitereproduction will result from the marking impulses of the stylus 53moving in synchronism with the transmitter scanner.

The reciprocating stylus mechanism is designed to have a small moment ofinertia and proportioned according to well known dynamic principles tobe substantially equi-responsive to the whole frequency band necessaryto translate the picture signals. Figure 7 is an enlarged detailcross-sectional view of the reciprocating stylus mechanism actuated bythe amature 53 which controls the movement of the stylus'rod 52 at theend of which is secured the stylus point 53. 'I'he stylus section 53which is heated by the coil 54 electrically connected to the battery 18,is preferably made of steel toresist wear. The stylus rod 52 ispreferably made of very iight material such as aluminum and is alsohollow to reduce its mass and inertial reaction.

'I'he scanner rod 52 is slidably supported in bushing at the end of thearm 48 and secured the spring 83. The normal distance of the styluspoint 53 from the record sheet 5| is adjusted by means of the screw 84.This adjustment is made by suitably positioning the barrel with respectto the pivot 64 on armature 63. The barrel 8| is slotted at itsmidportion to permit such variable positioning. The spring 83 maintainsthe pivoted relation of the barrel 8| with respect to the pin 64 intake,as determined by the adjustment of screw 84. In a practical unit, I usea distance of' .006 inch for'the stylus point 53 away from` sheet 5|corresponding to signal-off position. The signals corresponding to blackenergize the coils 1| of the electromagnetic structure 41 to' protectsthe stylus 53 from digging into the sheetl 5| for an especially intensesignal.

Figure 9 is a perspective view of the exterior of a facsimile receiverunit. The cable con-- tains the electrical connections for the motorstylus heater coil 54, and the rectied facsimile signals for therecording magnet structure 41.

y The positive reproductions of the transmitted picture are seen on theextended portion of the record sheet 5|. 'I'he case 81'for the unit mayhave a streamlined and pleasing appearance as shown, particularly forhome use where the unit should have a pleasing appearance and harmonizewith the surrounding furniture. For aircraft installations and otherapplications where definite length or width requirements are had, thearrangements of the motor and governor may be varied from theillustrated positions without departing from the spirit or scope of thepresent invention.

Although I have illustrated a preferred embodiment of my presentinvention, modifications will become evident to those skilled in the-artand accordingly I do not intend to be Hunted except as set forth inthe-following claims.

I claim:

1. In a facsimile recording unit the combination of a stylus arm havinga. stylus at one end. with means for reciprocating said stylus against arecord sheet including a rod armature, pivotally connected to saidstylus arm and electromagnetic means for actuating said armature inaccordance with received facsimile signals comprising a magnetic polestructure having a substantially uniform eld magnet portion and havingan air gap individually cooperating with each end of said rod armature,coilmeans, responsive to said signals for variably controlling saidmagnetic field to correspondingly actuate said amature, said rodarmature being pivotally and centrally supported within said polestructure and between said air gaps; means for moving said stylus insynchronism with the transmitter scanning operations comprising a membersecured to said .reciprocating means, and mechanism for oscillating saidmember; and means for controlling the maximum excursion of said styluscomprising two opposed screw members positioned adjacent the free endofA said armature, adjustably positionable with respect to said freearmature end whereby said screw members abut said armature when saidarmature vibrates a predetermined degree.

2. In afacsimile recording unit the combination of a stylus arm having astylus at one end, with means for reciprocating said stylus against aIrecord sheet including an armature connected to said stylus arm, andelectromagnetic means a for actuating said armature in accordance withreceived facsimile signals comprising a magnetic pole structure having asubstantially uniform magnetic field; means for translating the motionof said armature to said stylus arm comprising a hollow tube and a pivotconnecting said hollow tube to an end of said armature, the free end ofsaid stylus arm being secured to one end of said tube and positined tohold said stylus adjacent said record sheet; and means enclosed in saidhollow tube for adjusting the distance betlween said stylus and saidpivoted armature en 3. In a facsimile recording unit, the combination ofa stylus with means for reciprocating said stylus against a record sheetincluding a rod armature connected to saidvstylus, and electromagneticmeans for actuating said armature in accordance with received facsimilesignals comprising a magnetic pole structure having a substantiallyuniform magnetic field, and having an air gap individually cooperatingwith each end of said rod armature, said rod armature being plvotallyand centrally supported within said pole structure and between said airgaps and a first and second solenoid surrounding portions of said rodarmature and being responsive to said signals for variably controllingsaid magnetic field to correspondingly actuate said armature; means fortranslating the motion of said arma.- ture to said stylus comprising atube and a pivot connecting said tube to an end of said armature tomaintain said stylus in a spaced relation-with respect to said armatureand adjacent said record sheet; and means for adjusting the distancebetween said stylus and said armature comprising Aa barrel supportingsaid tube pivotconnection and secured to the end of said tube remotefrom said stylus, a spring enclosed in said barrel for mechanicallybiasing said barrel and tube away from said pivot towards the recordsheet and means for counteracting said spring bias and maintaining saidbarrel in a predetermined relation with respect to said pivot. i

4. In a .facsimile recording unit, the combination of a stylus withmeans for reciprocating said stylus against a record sheet including arod armature connected to said stylus, and electromagnetic means foractuating said armature in accordance with received facsimile' signalscomprising a magnetic pole structure having a substantially uniformmagnetic field, and having an air gap individually cooperating with eachend of said rod armature, said rod armature being pivotally andcentrally supported within said pole structure and between said air gapsand a ilrst and second solenoid surrounding portions of said rod amatureand being responsive to said signals for variably controlling saidmagnetic field to correspondingly actuate said armature; means fortranslating the motion of said armature to said stylus comprising a tubeand a pivot connecting said tube to an end of said armature A tomaintain said stylus in a spaced relation with respect to said armatureand adjacent said record sheet; a bracket secured to said structurecontaining means for slidably supporting said tube; means for movingsaid stylus in synchronism with the transmitter scanning operationscomprising a member secured to said reciprocating means, and mechanismfor oscillating said member; and means for adjusting the distancebetween `said stylus and said armature comprising a'barrel slidablysupporting said tube pivot connection and secured to the end ofsaid tubere- Imote frm said stylus, a spring enclosed in said barrel formechanically biasiiigsaid. barrel and tube away from said pivot towardsthe second sheet, and screw means for counteracting said spring bias andmaintaining said barrel in a predetermined relation with respect to saidpivot.

5. In a facsimile recording unit, the combination of a stylus with meansfor reciprocating said stylus against a record sheet including a rodarmature connected to said stylusland electromagnetic means foractuating said armature in accordance with received facsimile signalscomprising a magnetic pole structure having a substantially uniformfield magnet portion and having an air gap individually cooperating witheach end of said rod armature, a pin passing through the central regionof said armature for pivotally supporting said armature within said polestructure, and a iirst and second solenoid surrounding opposite endportions of said rod armature and being responsive to said signals, forvariably controlling said magnetic fleld to correspondingly actuate saidarmature; means for translating the motion of said armature to saidstylus at substantially right angles with respect tothe armaturemovements comprising a tube anda `pivot connecting said tube to an endof said armature projecting from said structure, to maintain said stylusin a spaced relation with respect to said armature and adjacent saidrecord sheet; a bracket secured to said structure containing means forslidably supporting said tube; means for moving said stylus insynchronism with the transmitter scanning operations comprising a shaftsecured to said reciprocating means, and mechanism for oscillating saidshaft including a cam; vmeans for adjusting the distance between saidstylus and said armature; and meansfor controlling the maximum excursionof said stylus.

` WILLIAM G. H. FINCH.

